We seem to have a few things in commonMy photography genre is spontaneous,
I am also of a wholly trio plus school and believe less is more, 14-24, 24-70, 70-200, add a 200-500, hire anything else.
My vision going forward is i am attracted to smaller lighter, one day, hence i like your kit for what you do.
I am waiting to see what the Z8 has to offer, if it has at least 12-14 fps is small light like the Z7II then its good by Z9 in a heart beat, i am not defendant of auto 3 D tracking.
I find my D850 to be the best do anything well all round tool, with image files i just love. Its not a Z9 dedicated in tracking and speed etc.
The Z9 i have is a toe in the water of mirror less, yes its larger heavier, similar image files to the D850, it offers for me at 45mp a OPTIONAL significantly higher frame rate and the key advantage of super fast focus attack speed, the rest for me is optional or in cases overkill and to complicated to enjoy, but that's me, some like a Muscle car others a Toyota Camry LOl.
16mm F2.8 fish eye...........Its a stunning lens, very sharp, has a 180 degree filed of view, brilliant for Astro, landscape, seascape, and especially creative photography, street photography, my friend used 2 of them on DX cameras to do a creative wedding shoot, an amazing lens if you know how to use it to its potential. It was made originally for Astro many years ago, its super tiny and light, its unique and a bit like the 19mm Tilt Shift to use, that lens is as good as it gets for ultimate sharp landscape architectural shots but you also need to know how to use it to its potential and harness its magic.
I too am a believer of the trinity concept (less is more kind of approach). The classical 12-24, 24-70, 70-200 however doesn't apply to me anymore, since my 24-120mm covers a big past of the 24-70+700-200 combo. That's why I thinking about the 100-400 (as a replacement for my 70-200).
A lot of D500 shooters are waiting for the Z8 / Z90 or what ever it will be called.. including me.
I strongly agree with your statement "If i cant nail what i want with what i have i need to question how and what i am doing."
We share the same passion for the D850. but I have to admit, right now, a lighter Z success will be very welcomed
"I paint with light, the lenses are my brushes nothing more or less" well said.
I struggle with wide angle, having primarily experience with telephoto lenses.. that why I think the 16mm Fish eye will be quite a challenge for me. That's why I also rarely use the ultra wide lens of my iPhone. I guess my eyes are used to telephoto DOF. Who knows, maybe one day I'll rent it and give it a try.